Prompt
The prompt or production notes the author already shared in public.
Build an interactive 3D jelly pufferfish (fugu) as a single self-contained HTML page using three.js from a CDN.
The fish is a soft-body gummy sitting on a table. Model the body as one closed icosphere-topology skin with two rest shapes per vertex: a calm fish (blunt round head, body tapering to a short tail stalk, slightly flattened belly) and a fully inflated ball (sphere with the same tail stalk sticking out). Blend between them with an "inflation" value. Simulate with XPBD at a fixed 1/600 s substep (frame-rate independent): edge-length constraints, a global volume constraint, a soft global shape-matching pull toward the blended rest shape (rotation via polar decomposition, gently leaning upright), ground collision with friction, and damping applied to the wobble (velocity relative to the body's mean) so it jiggles but settles in about a second. Render with one Loop-subdivision pass for a smooth surface.
Behaviour: tapping the fish startles it. It gulps air three times (mouth opens on each gulp, small overshoot) until it is a round ball, stays puffed about 4 seconds, then slowly deflates while blowing iridescent bubbles from its mouth. Dragging grabs and stretches the jelly locally; dragging empty space orbits the camera; wheel or pinch zooms.
Details: ~260 soft spines that lie flat and hidden when calm, pop up one by one (staggered) as it inflates, wobble on their own springs, bend against the table, and lift the ball so it stands on its spines. Big glossy eyes (gold-green iris, large pupil, white catchlight) that follow the cursor. Puckered lips with a tiny white beak. Translucent ray-striped fins: fluttering pectorals, swaying tail fan, rippling dorsal and anal fins, all faster when alarmed. Dark freckles on the back, pale belly, a few air bubbles trapped inside the jelly.
Look: MeshPhysicalMaterial with transmission, clearcoat and sheen for a candy-gummy look; a soft environment map; a soft colored shadow with a faint caustic on a floor that matches the page background. Flavour presets Yuzu, Ramune, Momo, Matcha. Editorial "Material Studies" layout: big italic serif title "Fugu Jelly.", a side panel with flavour swatches, Firmness and Wobble sliders, Startle / Calm / Reset buttons, ¼ speed and Sound toggles, and live readouts for volume, spine angle and mood. Synthesized WebAudio sounds for gulps, a boing on tap, a hiss while deflating and tiny bubble pops. Responsive down to phone width.
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Interactive 3D squishy jelly pufferfish in the browser
Sonnet, why so expensive when Opus is right there? 🐡
Claude Opus 5.5 vs Claude Sonnet 5.5. Same task - make a jelly fugu you can squish and puff up right in your browser
Claude Opus 5.5 - 7.45$
Claude Sonnet 5.5 - 6.20$
Just $1.25 apart, but I like the Opus result much more: more detail on the body, better-defined spikes and fins, and the fish itself looks more like jelly. It’s more fun to look at and squish
Sonnet made something cute too, but at almost the same cost, I’d pick Opus
Honestly, I don’t get why Sonnet ended up costing so much. It’s supposed to be the cheaper option, but the savings here are tiny
Would you pay the extra 1.25$ for the Opus result? 👀